This invention relates to a horizontal refrigerator which has a showcase installed on the top surface of a thermally insulated box.
As a horizontal refrigerator for use in a kitchen of a restaurant and the like, which has a show-case installed thereon for refrigerating food materials such as food materials for sushi, vegetables and the like, one described, for example, in Japanese Unexamined Patent Publication No. Hei 11-294925 exists. The horizontal refrigerator described in this publication document has a refrigerating chamber defined within a thermally insulated box, which constitutes the body of the refrigerator such that cold air cooled by a cooler constituting a refrigerating mechanism together with a compressor and a condenser is supplied in the refrigerating chamber by a built-in fan to cool down the refrigerating chamber. On the bottom of a show-case having a thermally insulated structure, installed on the top surface of the thermally insulated box, an opening is formed at a position corresponding to an opening formed through a ceiling of the thermally insulated box, such that cold air within the refrigerating chamber is introduced into a storage chamber defined in the show-case through both openings to cool the storage chamber. The show-case is formed with an output port from an upper portion to a front portion, and the output port is constructed to be opened and closed by a slidable door.
With the foregoing horizontal refrigerator, a large number of preliminarily prepared food materials and the like are contained in the storage chamber of the show-case, and taken out from the storage chamber, when cooked, and cooked on the top surface of the thermally insulated box in front of the show-case. In this event, since the refrigerator employs a cooling method which forcedly circulates cold air by convection into the refrigerating chamber and storage chamber using the built-in fan, a problem is pointed out that food materials and the like contained in the storage chamber is dried by a flow of cold air and are likely to lose its freshness. Accordingly, there has been proposed a method which involves providing a show-case with a thermally conductive panel which is cooled by cold air introduced from a refrigerator, and cooling down a storage chamber by natural convection of the cold air cooled by the thermally conductive panel. While the natural convection based cooling method prevents food materials and the like within the storage chamber from drying, the thermally conductive panel cannot be disposed at an output port formed through the show-case, resulting in a problem of a limited area cooled down by the panel, and a low cooling efficiency.
Also, since the refrigerating chamber is in communication with the storage chamber through the openings, moisture in the air in both chambers clings to the cooler for cooling both chambers as frost. Moreover, since a large amount of warm air including moisture flows into the refrigerating chamber from the storage chamber of the show-case which is often opened and closed by the slidable door, a large amount of frost clings to the cooler in a short time, causing a problem of insufficient cooling by the cooler and low cooling capability. Further, a problem is also pointed out that since the output port of the show-case is formed from an upper portion to a front portion, cold air near the bottom flows out when the slidable door is left open, and warm air flows into the storage chamber and refrigerating chamber, temperature in both chambers is likely to rise.
The horizontal refrigerator described above is constructed to close the opening formed through the ceiling of the thermally insulated box with a lid such that the show-case can be removed from the thermally insulated box to use only the refrigerator section (only the thermally insulated box). However, the heat insulating performance is low at the opening closed by the lid, causing a problem of low cooling capability as compared with a product which is not provided with an opening through the top of a thermally insulated box. Also, a portion around the opening closed by the lid has a lower strength as compared with a product which is not provided with an opening on the top of a thermally insulated box, resulting a tendency for deformation of the top surface of the box, a dent of the lid and its surroundings, and the like, and resulting inconvenience in cooking on the thermally insulated box.
Food materials and the like within the show-case are cooled generally within service hours, and not out of the service hours. However, with the conventional horizontal refrigerator, even when the show-case is not used, cold air in the refrigerating chamber flows out from the opening of the thermally insulated box to the storage chamber, causing a problem, as pointed out, that a cooling efficiency lowers in the refrigerating chamber, a larger load resulting therefrom is applied to the compressor, and larger electric power is consumed to increase running costs. In the structure in which the opening can be closed by the lid in the foregoing manner, cold air can be prevented to some degree from flowing out from the refrigerating chamber into the storage chamber. However, it is difficult to completely eliminate outflow of cold air through a gap between the lid and the thermally insulated box. Even if the lid is made in a thermally insulated structure, thickness of the heat insulating material is less than thickness of a heat insulating material of the thermally insulated box to cause heat exchange to the storage chamber, thereby failing to prevent an increase in running costs due to a larger load on the compressor.
The present invention has been proposed in view of the disadvantages mentioned above to preferably solve them, and it is an object of the invention to provide a horizontal refrigerator which is capable of preventing lower cooling capability, and also capable of preventing a lower cooling efficiency for a refrigerating chamber when a show-case is not in use.
To overcome the problem and preferably achieve the intended object, the present invention is characterized by being a horizontal refrigerator for cooling a refrigerating chamber defined inside a thermally insulated box by a cooler of a cooling mechanism, and having a show-case disposed on a top surface of the heat insulating box, wherein:
the show-case comprises an outer box, an inner box disposed within the outer box spaced by a necessary space therefrom and a heat insulating material filled between both boxes, an opening is formed only in a top portion thereof, and
a cooling pipe connected to said cooling mechanism is disposed in contact with an outer surface, where said heat insulating material is filled, of said inner box, such that a storage chamber defined inside said show-case is cooled by said cooling pipe.